Aptitude - Probability - Discussion
Discussion Forum : Probability - General Questions (Q.No. 5)
5.
Three unbiased coins are tossed. What is the probability of getting at most two heads?
Answer: Option
Explanation:
Here S = {TTT, TTH, THT, HTT, THH, HTH, HHT, HHH}
Let E = event of getting at most two heads.
Then E = {TTT, TTH, THT, HTT, THH, HTH, HHT}.
 P(E) = |
n(E) | = | 7 | . |
| n(S) | 8 |
Discussion:
121 comments Page 5 of 13.
Riems said:
1 decade ago
Is there any direct method for calculating it? Because calculating n(e) may get confused in the exams time.
Manju said:
1 decade ago
How many times a man can tossing a coin so that the probability of atleast one head is more than 80%?
Sambit said:
9 years ago
But in explaining in the event there is TTT is included that is the wrong HHH is included is correct.
Afsha said:
7 years ago
At most means not more than;
Here, it's not more than 2. Thus, n(E) = 3.
Therefore, p(E) = 3/8.
Here, it's not more than 2. Thus, n(E) = 3.
Therefore, p(E) = 3/8.
Chelsia said:
2 years ago
We can get quickly the number of events like 2 to the Power of (number of coins).
I.e 2'3=> 8.
I.e 2'3=> 8.
(7)
Abhijit said:
1 decade ago
Total no of probabilities= 2^3 =8
for 2/1/0 heads probability is =7(only 1 left HHH)
for 2/1/0 heads probability is =7(only 1 left HHH)
Trusha said:
10 years ago
Hi guys I'm totally confused about 'or' and 'and' concept can anyone help please?
Kishore said:
1 decade ago
If the meaning of unbiased coin is different coins then the answer is correct.
Asmi said:
2 years ago
At most means not more than 2 heads.
And at least means more than 2 heads.
And at least means more than 2 heads.
(24)
Arnika said:
7 years ago
I can't understand this, please anyone help me to get the answer clearly.
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